My only issue with Duke (but Witchaven Hero breaks this) is the use of Doom engine characters like Doomguy, Corvus, and the three heroes of Cronos, so in a sense, ChexMan would fit the bill but Duke wouldn't, though I'm not against Duke at all since he's awesome, but also the point would open to "Why not Strife guy? Why not Lo Wang? Why not that guy in Powerslave\Exhumed." So there's my two cents.